Taking oral contraceptives can blunt a woman's sexual drive long after she
stops taking the pill -- even permanently -- a prominent sexual dysfunction
researcher says in today's edition of NewScientist.

"There's the possibility it is imprinting a woman for the rest of her
life," Dr. Irwin Goldstein said in the publication.

Doctors already know that for some women, the drop in testosterone levels
that comes with taking the pill results in a loss of libido.

The drugs curb the production of testosterone in the ovaries and raise
levels of sex hormone-binding globulin, which takes testosterone out of play,
according to NewScientist. But doctors have always assumed that these effects
were temporary and levels would return to normal soon after a woman stops
taking the pill.

Dr. Goldstein and his fellow researchers at Boston University studied sex
hormone-binding globulin levels in 125 young women at a sexual dysfunction
clinic every three months over a year. Of these subjects, 62 were taking the
pill, 40 had taken the pill before, and 23 had never taken it.

The researchers found that the levels were seven times as high in the pill
users as they were in women who had never taken them. The women who stopped
taking the pill had lower levels, but these were still three or four times as
high as in the women who had never taken oral contraceptives, they reported at
a meeting of the American Association of Clinical Endocrinologists in
Washington last week.

This is not the first time Dr. Goldstein has sounded the alarm about the
pill and libido. In a 2003 interview, he said that testosterone leads both men
and women to enjoy sex. But a woman taking oral contraceptives may be left
with only a third of the hormones to make sex enjoyable.

"For many women who are young, it is a sort of irony that (birth
control pills are) supposed to bring on sexual freedom, and it robs women for
the biology to have sexual activity."

Dr. Elaine Jolly, medical director of Ottawa's Shirley E. Greenberg Women's
Health Centre, said many women have found that their libido decreases when
they take oral contraceptives.

But she finds it surprising that Dr. Goldstein is suggesting that taking
the pill may affect a woman for life. Indeed, the subject has never come up in
the gynecological research community, she said.

About a third of all Canadian women of reproductive age are on the pill at
any one time, she said. Since oral contraceptives were introduced about 40
years ago, hormone levels in the pill have dropped considerably and doctors
now prescribe the lowest levels of hormones possible.

Dr. Jolly suggests that there may be problems with the study. All of the
women in the study were patients at a sexual dysfunction clinic, she points
out. "Obviously this was a biased sample."

She argues if there was some sort of permanent effect, more women would be
infertile -- women need testosterone to ovulate.

Besides, libido is not just predicated on hormones.

"The number 1 sex organ is the brain," said Dr. Jolly. "What
he is talking about is true. But it's not all or nothing."